热带水稻优异种质资源的表型遗传多样性分析

Genetic Diversity of Tropical Rice Germplasms Measured by Phenotypic Traits

有效管理和充分挖掘遗传多样性丰富的稻种资源对水稻育种具有重要意义。利用15个表型性状对来自9个热带国家和地区的127份热带水稻育种优异种质进行综合评价，比较分析不同来源热带水稻优异种质的表型差异和遗传多样性指数。结果表明：热带水稻种质资源表型性状差异明显，数量性状的变异系数为7.0%～23.8%，平均为12.04%，其中单株穗数比较大，谷粒长较小； Shannon-Wiener 多样性指数分析结果表明，15个表型性状遗传多样性指数变化为0.603～2.066，平均为1.579，其中每穗总粒数比较高，穗型较小；9个不同来源地的热带水稻资源多样性指数为0.780～1.547，平均为1.219。不同来源的热带水稻种质各性状变异范围较大，各性状间存在显著差异，遗传多样性指数较高，可进一步发掘优异资源和有利基因，为培育和筛选优良热带水稻品种提供亲本来源。

Effective management and fully exploration the rich genetic diversity of rice germplasm have an important guiding significance for rice breeding. Genetic diversity of 127 tropical rice breeding lines originated from 9 tropical countries and regions were analyzed and compared with 15 phenotypic traits. The results showed variation of phenotypic traits was obvious among tropical rice breeding lines.The variation coefficient of numerical traits was 7.0%-23.8%, with an average of 12.04%, and was relatively higher in panicles per plant, lowest in kernel length; the Shannon-Wiener diversity index of 15 phenotypic traits was 0.603-2.066, averaging at 1.579, which was relatively higher in total grain number per panicle, had the lowest in panicle type; the diversity index of 9 tropical countries and regions was 0.780-1.547, with the average of 1.219. There was significant difference among the phenotypic traits, higher genetic diversity index and large variation range in the tropical rice germplasm from different sources, excellent germplasm and favorable genes could be further explored to provide superior parental lines for screening and developing elite tropical rice varieties.